Well......my season has come to a close and I wanted to share some experiences I had testing a set of viper clutches on my winder. I'm not trying to sell anything or skew anyone's thinking, but rather want to start a communication and pass along some of my findings and opinions..........make of them what you will.
First a little history:
I have an RTX SE 129 which I broke in by the book. For the first 300 miles I drove the sled exactly as stated in the manual and conducted break in procedures verbatim. From 300-500 miles I stretched the sled out a little more, but still took if fairly easy conducting a few short blasts up to 100mph. At exactly 499 miles, I performed the first service, consisting of oil/filter change, grease job and a general look over. One thing I noted was the excessive amount of belt dust in the clutch department. Having owned 6 RX-1s and 8 apexes spanning over 50k miles, I remember thinking, " Wow, there's 10k worth of belt dust, which has accumulated in only 500 miles." At any rate, I cleaned and inspected the clutches and did not find anything out of the ordinary. I took the belt (8JP) off and upon close examination determined that it still appeared like new.
With a complete service, and the engine now broken in, I figured it's time to start riding this thing normal. The next day I headed out and after riding about 5-6 miles of trails, I got on the rr bed and held it at a constant speed of 100mph. A few stretches I held it WOT for about 1/2 a mile, but would back off to 100mph again. At approximately 519 miles......KAPOW!!!! The 8JP snapped in half like someone cut it in half with a saw. The clutches were smoking hot and I was unable to keep my hand on them for more than a couple seconds. The conditions were as follows: Temperature was 8 degrees Fahrenheit and conditions were a little soft due to a 6 inch snowstorm from 2 days prior. My apex could have sustained these speeds under these conditions without issue!
I put an 8dn on which I had as a spare from my apex days. I ran the 8dn from 519 miles to 748 miles, but took it off because it was leaving traces of black snot on my clutches from slipping. I went back to an 8JP and noticed better run ability which consisted of an extra 100 rpm and 3-4 mph extra top speed. Although the 8JP leaves a lot of belt dust, the performance gain coupled with the lack of the black snot caused by the 8dn make it a better belt in my opinion.
From this point I'm riding the sled normally.....racing a few buddies and conducting approximately 15 or so WOT runs in the mid 120's over a span of a few weeks in hard/cold conditions. One day, I leave my house and ride tight trails between 30-50mph for approximately 3 miles. I cross a road, power up to 50mph for about 300 feet, then I see the trail straighten out, so I give a little more throttle to about 80 mph and KAPOW!!! Belt broke in half like someone cut it with a saw, however this time blew a hole in my belly pan. I went from 748miles to 1032 miles for a total of 284 miles. Upon inspection, I notice the clutches are a little warm, but nothing to write home about. I have no idea what caused this.
At approximately 1098 miles, my Buddy lent me a set of viper clutches he had lying around (both primary and secondary) which I mounted on my winder. The primary clutch consisted of stock 15.6 rollers my Dalton weights and factory spring, while the secondary was left stock. (Spring set at 70 degrees, straight 43 helix) The only thing not factory in the secondary was the addition of shims behind the helix for overdrive. At this point, I still have not changed my busted belly pan so I fully intend to beat this thing like a red headed step sister and I fully anticipate blowing this belt to smithereens within 100 miles. To make matters worse, I figure now is a great time to try higher gearing in an effort to exacerbate things. Therefore I gear my sled up from a 21 top gear to a 22 top gear.
From 1098 miles to 1684 miles (586 miles) I did dozens, upon dozens, upon dozens of WOT runs from 1-2 miles in length, many back to back, hitting speedo speeds in the high 120's to low 130's with a best of 132 mph. I was running this sled harder than ever and anticipated blowing a belt every time I threw a leg over it, but it would not happen. I thought perhaps something else was possibly causing me to have such good luck. At 1684 miles, I put my stock Winder clutches back on and went for my last ride of the season. At approximately 1720 miles (30 miles later) under what I consider normal riding conditions..........KAPOW!!!! Another belt broke in half like someone cut it with a saw. The most amount of miles I got on a belt this winter was 586, all accumulated with viper clutches under the most strenuous conditions. I felt this option was worth a serious look, so the next day, I went to see my Buddy that lent me the clutches and purchased them.
A few things I noticed:
Viper clutches run hot, but not as hot as the factory winder clutches.
Viper clutches are more consistent. Winder clutches turn 8800 one stretch, then 9050 another stretch, followed by 8850 a third stretch. Viper clutches would bang 8900 all the time.
Are the viper clutches faster in a drag race? I don't know as all the testing was done while riding alone. All I can compare are top speeds, which in my opinion seem to be in the ballpark.
Do I think viper clutches are better? Based on my experiences, I think so, but will continue to test another season to be sure.
Next year I plan to only run the viper clutches solely and hope to do some tuning and compare racing results. Although I did not have good luck using the 8dn belt with winder clutches, many viper owners swear by it. I hope to try 8dn again, this time utilizing viper clutches and I'm curious what the results will hold.
Gents,
I'm bringing this post back up to life as I want to share some more testing information. I did not put the amount of miles I wanted to this year and hence my testing is not as lengthy as I would have liked so I was planning on waiting to report only at the end of the season. However, with all the posts discussing offset and different clutch setups etc, figured I'd write and report what I've found so far. Some of us still have some snow left, so perhaps we can put our heads together and figure out these belt blowers before the season ends. Here is how my testing went:
Over the summer the ECU of my snowmobile took a plane ride to Turbo Dynamics for tune upgrade. I initially started the season at 1780 miles with a Viper secondary clutch however an electrical gremlin infected my snowmobile over the summer causing it to fall on rpm when wot. In an effort to troubleshoot the issue I wanted to rule out as many variables as possible so I went back to stock clutching. Long story short, I ended up finding the issue and fixing it, however i rode approximately 360 miles before finding the cure. Keep in mind over the course of this 360 miles I was simply trail riding. Once in a while I would hold it wot to check RPM and verify it was still falling and then resort back to zero to half throttle. During this time. I did not do any high speed runs or anything else out of the ordinary for that matter. One evening I'm driving along on the railroad bed at a consistent 75 miles an hour. My hand is glued on the throttle at 75 miles an hour, the railroad that is flat, I'm just trying to get home minding my business. At approximately 2138 miles..... kaaapooow. I open the sidepanel to find the bellypan is full of kevlar chicklets and the clutches are hot enough to cook eggs. I put a new 8jp and continue home disgusted.
At approximately 2200 miles I found the issue plaguing my sled. Long story short...I had a code locked in the ecu which was reaking havoc. Cleared code and boom, sleds been flawless ever since. This was the topic of another post, so no further discussion on this.
At 2240 miles I put back my viper secondary to continue testing. Keep in mind the belt already has 100 miles on it so 25% of its life is already pooched. At any rate I put stock front primary clutch blu/brn/blu spring and Dalton weights set at 75.7 grams. Rear viper secondary clutch with stock 43 degree helix and stock winder secondary spring set at 60 degrees. My plan at this point is to run soft springs and light weights in an effort to create the least amount of belt heat as possible.
I took a 3 day bag trip and headed to an area where they were announcing temps in the 40s. First day riding was great, sunny blue skies temps were in the mid-40s, trails were gray and slushy. Every turn was like riding through sugar. The sled would swap back and forth upon a turn approach, then a blast of throttle while exiting would send a rainbow of slush into the bushes. Yeehaaa... a few wot burns high 120s, low 130s, great day. Second day, morning was cooler, couple snaps...once to 132, then another to 133 mph. Afternoon temps hit 50f riding fast trails 75-80 and lots of lakes same speeds. Third day temps were 25f with fresh 3-4 inches of powder, did 30-40 miles of river with some slushy spots. Trip was 600 miles, hot temps, same belt.
Following week, my Buddy calls me to do some racing. He has a cat with a big tune. Whatever money can buy, he has it...it is on point and f&ckin fast.
I put a gallon of vp116, 9 gallons of 93, zeroed the trip and headed out for battle. We would grab it at 80 mph and hold wot anywhere from 1/2 to 1.25 miles at a time. Then, roll through a corner at 85-90, get some wind through the clutches and next stretch bang off again until the next corner, roll around the corner 85-90 then bang off down the next straight. Rr bed was rough, but every hit we were deep into 120s. We did this over and over and over, back to back to back for a cumulative 35-40 miles. Did some fast trail riding in conjunction with all this and I had 106 miles on the trip upon my arrival home. I took the belt off and examined it in amazement...... I ran the ever living f&ckin tar out of this thing and the belt still looked new. I couldn't believe it!!
Unfortunately, there is a downside. Although I have found the belt blowing cure and my current setup is docile, fuel efficient snd trail friendly, it lacks some drag racing prowess!!
Heres why.......I'm running 285hp, my Buddy 275hp and from 100mph to 120mph he could put 2 lengths on me. Hence, I think the viper secondary is a little slower and/or my setup sucks??? Trail riding, it bangs 9050 and stays there, but when conducting back to back runs, the belt gets hot/sticky, hits 9050, drops to 8750, then earns back 9050. This delay is what would cost me my 2 lengths. Next step I'll be installing stiffer springs and heavier weights to seek redemption and will post if the belt still holds.
As I write this, my sled has 3130 miles. The belt has 992 miles, 890 of which have been with the viper secondary. This is a world record for me. No doubt, the viper secondary runs cooler and is easier on belts. The only question lingering is if I can make it fast??? Hopefully I get a chance to conduct more testing before the snow melts.
